Preservation of the anal transition zone in ulcerative colitis. Long-term effects on defecatory function

Incidence and Risk Factors of Cancer in the Anal Transitional Zone and Ileal Pouch following Surgery for Ulcerative Colitis and Familial Adenomatous Polyposis

Proctocolectomy with ileal pouch-anal anastomosis is the intervention of choice for ulcerative colitis and familial adenomatous polyposis requiring surgery. One of the long-term complications is pouch cancer, having a poor prognosis. The risk of high-grade dysplasia and cancer in the anal transitional zone and ileal pouch after 20 years is estimated to be 2 to 4.5% and 3 to 10% in ulcerative colitis and familial polyposis, respectively. The risk factors for ulcerative colitis are the presence of pre-operative dysplasia or cancer, disease duration > 10 years and severe villous atrophy. For familial polyposis, the risk factors are the number of pre-operative polyps > 1000, surgery with stapled anastomosis and the duration of follow-up. In the case of ulcerative colitis, a pouchoscopy should be performed annually if one of the following is present: dysplasia and cancer at surgery, primary sclerosing cholangitis, villous atrophy and active pouchitis (every 5 years without any of these factors). In the case of familial polyposis, endoscopy is recommended every year including chromoendoscopy. Even if anal transitional zone and ileal pouch cancers seldom occur following proctectomy for ulcerative colitis and familial adenomatous polyposis, the high mortality rate associated with this complication warrants endoscopic monitoring.

A comprehensive review and update on ulcerative colitis. Dis Mon 2019;65:100851. [PMID: 30837080 DOI: 10.1016/j.disamonth.2019.02.004]

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disorder of the colon that causes continuous mucosal inflammation extending from the rectum to the more proximal colon, with variable extents. UC is characterized by a relapsing and remitting course. UC was first described by Samuel Wilks in 1859 and it is more common than Crohn's disease worldwide. The overall incidence and prevalence of UC is reported to be 1.2-20.3 and 7.6-245 cases per 100,000 persons/year respectively. UC has a bimodal age distribution with an incidence peak in the 2nd or 3rd decades and followed by second peak between 50 and 80 years of age. The key risk factors for UC include genetics, environmental factors, autoimmunity and gut microbiota. The classic presentation of UC include bloody diarrhea with or without mucus, rectal urgency, tenesmus, and variable degrees of abdominal pain that is often relieved by defecation. UC is diagnosed based on the combination of clinical presentation, endoscopic findings, histology, and the absence of alternative diagnoses. In addition to confirming the diagnosis of UC, it is also important to define the extent and severity of inflammation, which aids in the selection of appropriate treatment and for predicting the patient's prognosis. Ileocolonoscopy with biopsy is the only way to make a definitive diagnosis of UC. A pathognomonic finding of UC is the presence of continuous colonic inflammation characterized by erythema, loss of normal vascular pattern, granularity, erosions, friability, bleeding, and ulcerations, with distinct demarcation between inflamed and non-inflamed bowel. Histopathology is the definitive tool in diagnosing UC, assessing the disease severity and identifying intraepithelial neoplasia (dysplasia) or cancer. The classical histological changes in UC include decreased crypt density, crypt architectural distortion, irregular mucosal surface and heavy diffuse transmucosal inflammation, in the absence of genuine granulomas. Abdominal computed tomographic (CT) scanning is the preferred initial radiographic imaging study in UC patients with acute abdominal symptoms. The hallmark CT finding of UC is mural thickening with a mean wall thickness of 8 mm, as opposed to a 2-3 mm mean wall thickness of the normal colon. The Mayo scoring system is a commonly used index to assess disease severity and monitor patients during therapy. The goals of treatment in UC are three fold-improve quality of life, achieve steroid free remission and minimize the risk of cancer. The choice of treatment depends on disease extent, severity and the course of the disease. For proctitis, topical 5-aminosalicylic acid (5-ASA) drugs are used as the first line agents. UC patients with more extensive or severe disease should be treated with a combination of oral and topical 5-ASA drugs +/- corticosteroids to induce remission. Patients with severe UC need to be hospitalized for treatment. The options in these patients include intravenous steroids and if refractory, calcineurin inhibitors (cyclosporine, tacrolimus) or tumor necrosis factor-α antibodies (infliximab) are utilized. Once remission is induced, patients are then continued on appropriate medications to maintain remission. Indications for emergency surgery include refractory toxic megacolon, colonic perforation, or severe colorectal bleeding.

Risk of Neoplasia After Colectomy in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Colorectal neoplasia can still develop after colectomy for inflammatory bowel disease. However, data on this risk are scare, and there have been few conclusive findings, so no evidence-based recommendations have been made for postoperative surveillance. We conducted a systematic review and meta-analysis to determine the prevalence and incidence of and risk factors for neoplasia in patients with inflammatory bowel disease who have undergone colectomy, including the permanent-end ileostomy and rectal stump, ileorectal anastomosis (IRA), and ileal pouch-anal anastomosis (IPAA) procedures.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane Library through May 2014 to identify studies that reported prevalence or incidence of colorectal neoplasia after colectomy or specifically assessed risk factors for neoplasia development. Studies were selected, quality was assessed, and data were extracted by 2 independent researchers.

RESULTS

We calculated colorectal cancer (CRC) prevalence values from 13 studies of patients who underwent rectal stump surgery, 35 studies of IRA, and 33 studies of IPAA. Significantly higher proportions of patients in the rectal stump group (2.1%; 95% confidence interval [CI], 1.3%-3.0%) and in the IRA group (2.4%; 95% CI, 1.7%-3.0%) developed CRC than in the IPAA group (0.5%; 95% CI, 0.3%-0.6%); the odds ratio (OR) for CRC in the rectal stump or IRA groups compared with the IPAA group was 6.4 (95% CI, 4.3-9.5). A history of CRC was the most important risk factor for development of CRC after colectomy (OR for patients receiving IRA, 12.8; 95% CI, 3.31-49.2 and OR for patients receiving IPAA, 15.0; 95% CI, 6.6-34.5).

CONCLUSIONS

In a meta-analysis of published studies, we found the prevalence and incidence of CRC after colectomy to be less than 3%; in patients receiving IPAA it was less than 1%. Factors that increased risk of cancer development after colectomy included the presence of a residual rectum and a history of CRC. These findings could aid in development of individualized strategies for post-surgery surveillance.

The natural history of anal transition zone inflammation and possible relationship to pouchitis: a long-term longitudinal study

AIM

Reservoir ileitis (pouchitis) is the most common complication after pelvic pouch surgery for ulcerative colitis and the aetiology remains largely unknown. The anal transition zone (ATZ) contains the only remaining colonic epithelium after ileal pouch anal anastomosis (IPAA) and may provide important clues as to whether ulcerative colitis and pouchitis share a common pathogenesis. The aim of this study was to evaluate longitudinally the long-term histological changes in the ATZ and their relationship to the incidence of pouchitis.

METHOD

Patients with a double-stapled IPAA for ulcerative colitis at an academic medical centre with at least 10 years of clinical and histological follow-up were identified from a prospective database. Annual ATZ and pouch biopsies were taken and interpreted by two expert gastrointestinal pathologists. ATZ histological variability score, the incidence of pouchitis, and function were correlated over time. ATZ biopsies were scored from one to three based on the extent of inflammation.

RESULTS

Sixteen of the 114 patients having IPAA fulfilled the criteria for admission to the study. There were 179 biopsies of the ATZ. All exhibited variability in ATZ histology over time and 81% had a 2-unit change in their inflammatory score. There was no correlation between pouchitis and histological severity score of the ATZ. Similarly, function over time did not vary with the intensity of ATZ inflammation.

CONCLUSION

ATZ inflammation varies substantially over time in most patients. But these changes from year to year did not correlate with function or the occurrence of pouchitis.

Low anterior resection syndrome (LARS): cause and effect and reconstructive considerations

Between 25 and 80% of patients undergoing a low or very low anterior resection will suffer postoperatively, from a constellation of symptoms including fecal urgency, frequent bowel movements, bowel fragmentation and incontinence, collectively referred to as the low anterior resection syndrome (LARS). The etiology of LARS is multifactorial with the potential of sphincter injury during anastomosis construction, alterations in anorectal physiology, the development of a pudendal neuropathy, and a lumbar plexopathy with exacerbation of symptoms if there is associated anastomotic sepsis or the use of adjuvant and neoadjuavnt therapies. The symptoms of LARS may be obviated in part by the construction of a neorectal reservoir which may take the form of a colonic J-pouch, a transverse coloplasty, or a side-to-end anastomosis. This review outlines the factors contributing to LARS symptomatology along with the short- and medium-term functional results of comparative trials with the different types of neorectal reconstructions.

Morphology of the epithelium of the lower rectum and the anal canal in the adult human

The anal canal is an important body part clinically. However, there is no agreement about the epithelium of the anal canal, the anal transitional zone (ATZ) epithelium in particular. The aim of this study is to clarify the structure of the epithelium of the human lower rectum and anal canal. Intact rectum and anus obtained from patients who underwent surgery for rectal carcinoma were examined by light and scanning electron microscopy (LM and SEM). By LM, three types of epithelium were observed in the anal canal: simple columnar epithelium, stratified squamous epithelium, and stratified columnar epithelium. The lower rectum was composed of simple columnar epithelium. SEM findings showed stratified squamous epithelium that consisted of squamous cells with microridges, changing to simple columnar epithelium consisting of columnar cells with short microvilli at the anorectal line. LM and SEM observations in a one-to-one ratio revealed that the area of stratified columnar epithelium based on LM corresponded to the anal crypt and sinus. In conclusion, the epithelium of the human anal canal was fundamentally composed of simple columnar epithelium and stratified squamous epithelium. We found no evidence of the ATZ.

Postoperative defecatory function of an ileal pouch-anal anastomosis after a restorative proctocolectomy for ulcerative colitis: evaluation using fecoflowmetry

An ileal pouch is usually reconstructed as an alternative to a neorectum after a total proctocolectomy for ulcerative colitis (UC). However, the real defecatory function of an ileal pouch is uncertain. This study was designed to analyze the functional and clinical outcomes after a proctocolectomy and ileal pouch-anal anastomosis (IPAA) for UC using fecoflowmetry (FFM). Sixteen patients who underwent IPAA for UC between 1990 and 2005 were studied. They were evaluated by FFM, together with Kelly's clinical score (KCS), and anorectal manometric assessments were also performed. FFM showed that the fecoflow pattern (FFP) of 14 patients (87%) was the block type and of 2 patients (13%) was the segmental type. The clinical score and tolerance volume showed no improvement 1 year or more after IPAA. However, the value of the maximum fecal stream flow rate (Fmax) improved with time. FFM shows that the defecatory function improved after IPAA, and it may therefore contribute to a good long-term outcome after the surgery.

Completion mucosectomy for retained rectal mucosa following restorative proctocolectomy with double-stapled ileal pouch-anal anastomosis

INTRODUCTION

Colectomy with ileal pouch-anal anastomosis has become widely accepted and is now considered the procedure of choice for patients with ulcerative colitis (UC) as well as familial adenomatous polyposis (FAP).

DISCUSSION

The clear patient advantage of functional continence has pushed this procedure to the forefront in treating both UC and FAP. As a result, the procedure continues to evolve with recent debate centering on the question of whether to perform a double-stapled technique without rectal mucosectomy or a handsewn anastomosis following transanal mucosectomy. Although continence and complication rates continue to be hotly debated, it is understood that performing the stapled procedure does leave a rectal cuff, which carries with it the possibility of disease persistence or recurrence. As such, if the rectal cuff becomes symptomatic or dysplastic, it must be removed. This is accomplished by performing a transanal completion mucosectomy and reconstructing the ileal pouch-anal anastomosis.

Laparoscopic restorative proctocolectomy with ileal pouch anal anastomosis: a comparative observational study on long-term functional results

PURPOSE

Long-term results after laparoscopic ileal pouch anal anastomosis (IPAA) have not been thoroughly evaluated. Our study prospectively compares short- and long-term outcomes of laparoscopic and open IPAA.

METHODS

Between October 2002 and November 2007, 73 laparoscopic and 106 open IPAA patients were enrolled. Patient- and disease-specific characteristics and short- and long-term outcomes were prospectively collected.

RESULTS

There were no differences in demographics, treatment, indication, duration of surgery, and diversion between groups. Laparoscopic patients had faster return of flatus (p = 0.008), faster assumption of a liquid diet (p < 0.001), and less blood loss (p = 0.026). While complications were similar, the incidence of incisional hernias was lower in the laparoscopic group (p = 0.011). Mean follow-up was 24.8 months. Average number of bowel movements was 6.8 +/- 2.8/day for laparoscopy and 6.3 +/- 1.7 for open (p = 0.058). Overall, 68.4% of patients were fully continent at 1 year, up to 83.7% long term without differences between groups. Other indicators of defecatory function and quality of life remain similar overtime.

CONCLUSIONS

Laparoscopic IPAA confers excellent functional results. Most patients are fully continent and have an average of six bowel movements/day. When present, minor incontinence improves over time. Laparoscopy mirrors the results of open IPAA and is a valuable alternative to open surgery.

Laparoscopic restorative proctocolectomy with ileal pouch anal anastomosis: a comparative observational study on long-term functional results

PURPOSE

Long-term results after laparoscopic ileal pouch anal anastomosis (IPAA) have not been thoroughly evaluated. Our study prospectively compares short- and long-term outcomes of laparoscopic and open IPAA.

METHODS

Between October 2002 and November 2007, 73 laparoscopic and 106 open IPAA patients were enrolled. Patient- and disease-specific characteristics and short- and long-term outcomes were prospectively collected.

RESULTS

There were no differences in demographics, treatment, indication, duration of surgery, and diversion between groups. Laparoscopic patients had faster return of flatus (p = 0.008), faster assumption of a liquid diet (p < 0.001), and less blood loss (p = 0.026). While complications were similar, the incidence of incisional hernias was lower in the laparoscopic group (p = 0.011). Mean follow-up was 24.8 months. Average number of bowel movements was 6.8 +/- 2.8/day for laparoscopy and 6.3 +/- 1.7 for open (p = 0.058). Overall, 68.4% of patients were fully continent at 1 year, up to 83.7% long term without differences between groups. Other indicators of defecatory function and quality of life remain similar overtime.

CONCLUSIONS

Laparoscopic IPAA confers excellent functional results. Most patients are fully continent and have an average of six bowel movements/day. When present, minor incontinence improves over time. Laparoscopy mirrors the results of open IPAA and is a valuable alternative to open surgery.

Anal transition zone in the surgical management of ulcerative colitis

Preservation of the anal transition zone has long been a significant source of controversy in the surgical management of ulcerative colitis. The two techniques for restorative proctocolectomy and ileal pouch anal anastomosis (RPC IPAA) in common practice are a stapled anastomosis and a handsewn anastomosis; these techniques differ in the amount of remaining rectal mucosa and therefore the presence of the anal transition zone following surgery. Each technique has advantages and disadvantages in long-term functional outcomes, operative and postoperative complications, and risk of neoplasia. Therefore, we propose a selective approach to performing a stapled RPC IPAA based on the presence of dysplasia in the preoperative endoscopic evaluation.

Chronic inflammatory changes in the anal transition zone after stapled ileal pouch-anal anastomosis: is mucosectomy a superior alternative?

BACKGROUND

Chronic inflammation (CI) is commonly found in the anal transition zone (ATZ) after stapled ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). Yet, its impact on defecatory function and the need for a complete mucosectomy has not been completely elucidated. This study aims to evaluate the long-term functional outcomes of patients with CI of the ATZ after stapled IPAA in comparison with mucosectomy patients.

METHODS

Between June 1987 and November 2007, 66 UC patients were found to have CI of the ATZ after stapled IPAA and were compared with 228 UC patients who underwent mucosectomy with hand-sewn (HS) IPAA. Patients were mailed a questionnaire to assess defecatory function and quality of life. Data were analyzed prospectively.

RESULTS

No differences were observed in age, sex, number, or consistency of bowel movements (BMs) between groups. Complete continence was reported by 90.3% of CI and 66.8% of HS patients (P < .001). The CI group also had a significantly lower rate of major incontinence (P < .001). Functional parameters in favor of the CI group included the ability to discriminate between gas and stool (P < .001), the use of protective pads during both the day and the night (P < .001), dietary modifications in the timing of meals (P < .001) and type of food (P = .005), and the presence of perianal rash (P = .019). In the CI group, more patients rated their quality of life as improved from before the operation (P < .001).

CONCLUSIONS

Preservation of the ATZ, even in presence of persistent inflammation, confers improved continence, better functional outcomes, and superior quality of life.